The mechanisms of association between
obesity and the related metabolic disturbances in general and
insulin resistance in particular are extensively studied. Taking into account a key role of adipose tissue
insulin resistance in the development of systemic
obesity-related
insulin resistance, the estimation of mechanisms linking increased adiposity and impaired
insulin signaling in adipocytes will allow to develop novel prophylactic and therapeutic approaches to treatment of these states. A number of
trace elements like
chromium,
zinc, and
vanadium have been shown to take part in
insulin signaling via various mechanisms. Taking into account a key role of adipocyte in systemic
carbohydrate homeostasis it can be asked if
trace element homeostasis in adipose tissue may influence regulatory mechanisms of
glucose metabolism. We hypothesize that caloric excess through currently unknown mechanisms results in decreased
chromium,
vanadium, and
zinc content in adipocytes. Decreased content of
trace elements in the adipose tissue causes impairment of intra-adipocyte
insulin signaling subsequently leading to adipose tissue
insulin resistance. The latter significantly contributes to systemic
insulin resistance and further metabolic disruption in
obesity. It is also possible that decreased adipose tissue
trace element content is associated with dysregulation of
insulin-sensitizing and proinflammatory
adipokines also leading to
insulin resistance. We hypothesize that
insulin resistance and
adipokine dysbalance increase the severity of
obesity subsequently aggravating alteration of adipose tissue
trace element balance. Single indications of high relative adipose tissue
trace element content, decreased Cr, V, and Zn content in obese adipose tissue, and tight association between fat tissue
chromium,
vanadium, and
zinc levels and metabolic parameters in
obesity may be useful for hypothesis validation. If our hypothesis will be confirmed by later studies, adipose tissue
chromium,
vanadium, and
zinc content may be used as a prognostic
biomarker of metabolic disturbances in
obesity. Hypothetically, development and approbation of drugs increasing adipose tissue
chromium,
vanadium, and
zinc content may help to achieve better metabolic control in
obesity and
obesity-related
insulin resistance. However, stronger basis is required to prove our hypothesis. In particular, future studies should investigate the influence of
obesity severity of adipose tissue
trace element content, estimate the association between adipose tissue metals and metabolic parameters, and highlight the mechanisms involved in these changes. Both in vivo and in vitro studies are required to support the hypothesis.